We developed a high-permance liquid chromatograohy (HPLC) method for free fatty acids (FFAs) analysis in bile. In this method, FFAs were extracted from bile in a single step using an Isolute ^<TM>ODS cartride, derivatized with 9-anthrydiazome than (ADAM). ADAM was chosen because of its high reactivity with carboxylic acid at room temperature. Then, HPLC was used for separating and quantifying FFAs. This method proved to be simple and time-saving. The mean recovery of FFA added to human gallbladder bile was 97.6% and the detection limit was 100-250 pg. Using this method, we determined FFA concentrations in the gallbladder bile of 11 gallstone patients. The mean concentration of total FFA was 0.61(SD=0.41) mmol/L,and there was wide variation in the individual FFAs.Our result are somewhat discrepant from those of Shimada et.al. (1991). In their reprt, the total FFAs concentration in gallbladder bile obtained from gallstone patients in Fukuoka, Japan, was 1.30 (0.47) mmol/L (n=10), that is, twice the values we obtained in Niigata (0.61) mmol/L.The discrepancy in FFA concentrations, dispite other conditions such as disease, age and sex being almost identical between the two reports, is of particular interest from the viewpoint of geographical oncology ; Fukuoka is know as a low-risk for gallbladder cancer, and Niigata as a high-risk area. The possible relationship between the concentration or composition of FFAs and occurrence of gallbladder cancer should be assessed by further studies in various parts of the wold.